you will get conflicting answers as to whether they are a cross or a true breeding actual native variety from a certain river locality.
i have a feeling confusion has led to this and this can happen with common names.
my take is that people began breeding a green female with a red male because the greens were easier to breed. later they got called banjars.
when it is possible, and i beleive that yellow tails were also a native variety, that yellow tails existed prior to this and maybe had even been given the name banjar red.
you do have to wonder whether that common name banjar red was a marketing name idea for red crosses.
seeing as it is more a yellow fish than a red and why would a person name it a red might you ask?
well it is also possible that people desired reds so someone called a native yellow tail variety OR a cross a banjar "red" so it stood out from a common green and leaned somewhat more towards the red price.
if you look in the literature on the different colour varieties are are seperate species, which can be found in the stickys.
you will see that they did gene tests on what they came to receive as "banjars" and they were indeed the hybrid cross but i think they came from a farm and so may have been called banjars instead of say a grade 1.5 or whatever it was that was another marketing term.
i have not yet come across definate proof of this either way though, yet this kind of question has led to much fighting in the past.
the only real way to know would be to find information from someone that was around prior to the 80s and maybe they know that banjars with the yellow tail came from a river and they also know for sure it was not polluted with another genetic through human movement of fish sometime in the past 100 years or so.........do you see what i mean here?
Singapore also had yellow tails occurring in their water reservoirs from stocking which were later taken as broodstock by some farms.
this may or may not have been crosses also. government encouraged release of unwanted public person stock by the population and earlier farms had stocked the rivers with fish from breeding trials at a time that CITES was not letting them sell them.
so you probably would have had pure lines in there and green dumpings. that would depend on what stock the early farms used as breeding trials. I couldnt find which colours they were because the CITES papers i saw that mentioned the reservoirs being a source of stock did not differentiate which colours.
certainly by now, the man bred crosses have been around for decades now and this would be the case for some wild rivers having had the cross eventuate naturally yesterday because of some man performed stockings as well as some crosses being released.
you know, some farms release fish as a compensation..but some have gotten away with not adding the pure breed from that river.
that means in some rivers, it would be hard to know what is native old school pure lines or 1/2 fish back crosses for example.
if you do the math on the likelihood that they are a cross vs a real true old native line, id side with the cross.
i have seen yellow tails that are very pretty and would own one for sure and hey they are all related and can be judged by their owners tastes. if you want a pure bred fish, research the farms that stick to it.
crosses from whatever varieties will bring out a lot of desirable variation in the future the further they select over generations.
